“Consider that in 97 AD serious dissensions arose within the Church of Corinth and although the Apostle St. John was still living in Ephesus they appealed to the Roman Bishop, St. Clement, who wrote an authoritative letter to restore peace.”
Also notice that when theological disputes arose in New Testament times, no one went to Peter for the final answer. When Paul defended his Apostleship, he never once said, “Peter agrees”. In fact, when Peter and Paul disagreed, Paul rebuked Peter in public...
In his letters, Paul often cites scripture, but he never says, “Peter says...”
Who was the other man that St. Paul was referring to in Romans 15:20?
Throughout Scripture we see evidence of what did not need to be specifically articulated. Evidence of Peter's primacy can be found in Acts 15. It describes the Council of Jerusalem where the Apostle Peter speaks to resolve the conflict faced by the congregation at that time, namely on the issue of circumcision. When St. Peter made the decision that bound all the faithful, discussion ceased and the people fell silent. They unanimously accepted his decision. St. James, as the local Bishop then made the closing speech at the Council of Jerusalem, and conveyed Peter's decision.
Peace be with you